| Active principles | Rating | Bibliogr. | Expand | |
|---|---|---|---|---|
| 1 | Heterocyclic Compounds, 1-Ring | 100 | + | |
| 2 | Heterocyclic Compounds, 2-Ring | 76 | + | |
| 3 | Alkaloids | 31 | + | |
| 4 | Heterocyclic Compounds, 3-Ring | 31 | + | |
| 5 | Heterocyclic Compounds, Bridged-Ring | 13 | + | |
| 6 | Heterocyclic Compounds with 4 or More Rings | 9 | + | |
| 7 | Pyrans | 8 | + | |
| 8 | Acids, Heterocyclic | 2 | + |